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局部化模式和声波带间隙使用基于封闭和开放共振器的不同准周期结构
Ilyas Antraoui1, Ali Khettabi1, Mohammed Sallah2
1Laboratory of Materials, Waves, Energy and Environment, Department of Physics, Faculty of Sciences, Mohammed First University, Oujda, 60000, Morocco.
Scientific reports
|March 4, 2025
概括
准周期结构,如图伊-莫尔斯序列,为降低噪音和波导产生广泛的声波带间隙. 这些结构提供了超越传统周期设计的独特波浪操纵.
科学领域:
- 声学 声学 在声学上.
- 波浪传播 波浪传播
- 材料科学 材料科学 材料科学
背景情况:
- 准周期结构提供了在周期结构中找不到的独特波动操纵能力.
- 了解声波通过这些复杂结构的传播对于先进的应用至关重要.
研究的目的:
- 探索不同类周期序列 (Thue-Morse,Cantor,Rudin-Shapiro) 对声波传播的影响.
- 研究一维波导结构中的声传输特性和带间隙创建.
主要方法:
- 使用转移矩阵方法和有限元素方法进行分析.
- 研究了一维波导结构,基于Thue-Morse,Cantor和Rudin-Shapiro序列.
- 采用线性声学模型,忽略了更高阶模式和粘性效应.
主要成果:
- 准周期序列产生了带宽差距,具有许多局部状态 (狭窄的传输峰值).
- 与Rudin-Shapiro和Fibonacci序列相比,Thue-Morse序列展示了优越的声波带间隙创建和扩展.
- 图伊-莫尔斯,坎托尔和鲁丁-沙皮罗序列在带间隙内表现出显著的传输峰值,超过了斐波纳契序列.
结论:
- 准周期结构有效地控制声波传播,产生显著的频段间隙.
- 准周期序列的选择 (例如,Thue-Morse) 影响了声带间隙和传输的特征.
- 这些发现在低频噪声降低,声学过和波导方面有潜在的应用.
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